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By Zhang Y. D, Zhang R. X

A new decision-making approach of artificial neural network system with hierarchic structure is presented. The fundamentals of network topology, node functions and network training are introduced. A neural network system with hierarchic struct

Jan 1, 1998

This paper reviews an analytical model that defines the relationship of weight-weighted or volume-weighted average haulage distance with bench height and other related parameters; presents the optimum bench heights under various conditions in terms of minimising the weighted average haulage distance of ore/waste during the full lifetime of an open pit mine, and discusses the truck-haulage economics of mining open pits by high bench, specifically by 15 m, 18 m and 20 m bench through marginal analysis. The observations from these analyses disprove the previous conflicting assertions that the overall weighted average haulage distance either increases or decreases monotonically with bench height. It is concluded that: (i) an increase of bench height to 15 m from 12 m is likely to be viable under the general conditions of large-scale deep open-pit mines; (ii) the reduction of haulage cost is limited with the case of increasing bench height to 18 m from 15 m; and (iii) the feasibility of mining open pits by 20 m benches is generally questionable. These conclusions may serve as a useful guide for those who advocate open pit mining by high benches.

Jan 1, 1995

AustraliaÆs record-breaking drought, efforts towards environmental best practice and the current commodities boom is demanding water use and reuse as never before. Mining practices, processing, the remote communities and support industries require vast amounts of specific quality water. Sustainability of water use has been a key factor in mine development, expansion of existing operations and increasing profitability of processes involving water. Developments in water treatment technology have enabled the use of a range of processes to produce this water reliably at ever decreasing costs. This increasing acceptance of new technologies has seen seawater desalination, recycling of plant wastewater streams, municipal wastewater reuse and others to become commonplace. Processes including seawater and groundwater reverse osmosis (RO), low pH RO, thermal desalination, high rate clarification, brine water treatment, ion exchange and other advanced treatment technologies are now used as part of mining operations. This paper surveys the trends in water treatment for the mining industry both in Australia and internationally with a review of technologies and case studies of operating plants. The key technologies are explained with an emphasis on the specific requirements for mining operations û unusual raw water, process and operations limitations, environmental concerns, as well as harsh climate. Case study information from several mining operations is included.

Jan 1, 2006

The Australian mining industry has suffered from a decline in its public image during the past decade. This has occurred partly as a result of increased questioning of accepted social and economic values since the mid-1960s and the greater restrictions placed on industry since then, and partly ò from the industry's inability to effectively answer its critics. Public opinion surveys have shown the depth of the decline in the industry's community acceptability and highlighted those issues which people regard as disadvantages of mining. The industry's poor public image has contributed to the difficulties of attracting young people to take up professional careers in mining. All those involved in the industry have a responsibility to assist in activities designed to improve the industry community Acceptability.

Jan 1, 1981

By Hayashida O, Numata Y

Ultraviolet and infrared spectroscopic analyses and the extended lluckel molecular orbital method were applied to determine the electronic and binding states of 2-mercaptobenzothiazole and the adsorption system of 2-mercaptobenzothiazole on pyrite. 2-mercaptobenzothiazole exists rather in thione form than in thiol forru and the two adsorption peaks in solution were assigned to both 7t--?rt* transitions. 2-mercaptobenzothiazole chemically adsorbs on pyrite mainly due to forming the bond between iron (pyrite) and sulphur (2-mercaptobenzothiazole).

Jan 1, 1993

The global recession of the 1980s drove commodity prices down and intensified cost competition. The 1990s saw a restructuring of the mining industry with the survivors adopting new technology, significantly increasing workplace productivity and reducing capital and operating costs. Major changes in mining industry business strategies evolved in the late-1980s including the development of miner - supplier - manufacturer - partnerships, cultural changes in work practices and common goals between the partners to reduce the cost of production. These industry trends are putting new demands on mining machine manufacturers and dealers both on the `hard' side of the machine business, such as research and product development programs, and on the `soft' side in terms of business processes, use of human resources and communication. The paper describes several mining industry trends as identified by a large supplier to the industry, and discusses the impact they are having, and will have, on mining machine development and the provision of product support services to the industry.

Jan 1, 1995

By Johnston R. F

The factors which influence the reduction of chromite are investigated with special reference to Coobina chromite. This was compared with a South African chromite ore. The reduction characteristics are outlined and the reduction kinetics studied Temperature has the most significant effect, followed by particle size, silica addition and type of coal.Electron microprobe analysis of the products indicates that iron in the chromite is first reduced at temperatures above 1100°C, followed by chromium at around 1200°C. At temperatures greater than 1200°C metallic iron and chromium are formed simultaneously and subsequently give an iron-chromium-carbon alloy. It was observed that the metallic carbide contains a small amount of silicon. The decomposition of the chromite spinel was observed to pass through the FeO.Cr2O3, MgO.Cr2O3 and MgO.AI2O3 forms before slag formation. It is concluded that Coobina chromite is suitable for the production of ferrochrome if direct prereduction followed by intensive bath smelting is used.

Jan 1, 1994

By M Kuruppu

The paper explores the sustainability of the Australian mining industry, and the potential for application of a substitute fuel into existing mining operations. This alternative fuel biodiesel is produced from biological oils and not from refined hydrocarbons like the transport fuel diesel (petrodiesel). The fuel is compatible with all current diesel equipment with little to no modification and has many superior properties. As biodiesel is derived from biological sources it is æcarbon neutralÆ meaning there is no net carbon addition to the atmosphere when the fuel is burned. The current fuel, petrodiesel releases long stored carbon dioxide (CO2) and is of concern to Australian government targets which seek to reduce these emissions. The mining industryÆs unique reliance on petrodiesel is of particular interest when assessing the substitution of biodiesel into underground and open cut operations. The underground benefits of biodiesel see a reduction in the noxious emissions of carbon monoxide and diesel particulate matter, both contaminants which require extensive diluting ventilation to ensure safe levels. As biodiesel is both safer to store due to its higher flash point and produces less exhaust emissions, its occupational health and safety benefits in underground mines is clear. The use of biodiesel in open cut mines benefits the environmental sustainability aspects of the project. The formulation of national targets relating to carbon dioxide emission reductions promotes any measure to reduce CO2 within the mining environment. As the diesel engine is one of the least emission efficient (kWh/tonne CO2) energy sources on-site, its potential for reduction in CO2 at minimal cost is the greatest. By substituting the fuel, significant quantities of site emissions are reduced, thereby achieving the goals of improved site sustainability and the governmentÆs targets to reduce emissions. This aspect of gauging mutually beneficial relationship regarding government interests and mining industry profitability is the underlying outcome for this paper.

Jan 1, 2009

By Bailey DJ

Loader cut and fill stoping was first used at New Broken Hill Consolidated Limited mine in 1966. The equipment used included single boom pneumatic jumbos for drilling up- holes, diesel loaders for ore removal and diesel utility vehicles for rockbolting and servicing. Since 1966, there have been many modifi- cations and changes both in the equipment and stoping method. Twin boom pneumatic or hy- draulic drilling jumbos have replaced single boom pneumatic jumbos, electric loaders have replaced diesel loaders, diesel forklifts have replaced utility vehicles and "'flatbacking" has superseded uphole stoping. Concurrent with this has been the introduction of cable dowels in stope backs which has enabled loader cut and fill stoping to be used more extensiv- ely than in the past. There are now six loader cut and fill stopes at both mines and this paper traces the evolution of this method outlining the reasons for changes in technique and equipment.

Jan 1, 1982

By P Walton, L W. Armstrong, D P. Blair

Sydney is the capital city of NSW and has a population of approximately four million people. Eighty per cent of the cityÆs water is supplied by Warragamba Dam, which is situated some 75 kilometres south west of the city centre. A risk assessment was carried out on the dam and future predictions of water flows into the catchment area showed that there was a risk of a one in 700-year flood not being contained by the dam. The predicted loss of life and property damage warranted the construction of an auxiliary spillway on the eastern side of the existing dam to cater for any uncontrollable influx of water. A test blasting program was instigated and the blasting parameters were established that would lead to routine production blasting of the sandstone rock making it more cost effective to excavate. Blast induced vibrations were a concern to the owners and the dam wall and ancillary infrastructure was instrumented with sensitive vibration monitoring equipment during the test blasting phase of the operation. Once the blasting parameters were established from the testing program production blasting was carried out on a daily basis to maintain æstockpileÆ of fragmented ground for the excavation equipment. Blast vibration models were developed to predict vibration levels for more sensitive areas of the dam to give the operators more confidence in their operations. The blast induced vibration levels recorded did not cause any structural damage to the dam wall and the waveform frequencies of the blasting operation were much higher than that experienced during a recent earthquake. The integrity of the SCAÆs assets were at no time jeopardised.

Jan 1, 2001

By E Hogan, M Goodz, R Wright

The planning, permitting and monitoring procedures of the re-opening and rehabilitation of mine sites is an ongoing process which must continue throughout and beyond the life of the project. Both industry and government bodies must remain flexible to allow guidelines to be altered where and when necessary.To enable the successful re-opening of the Morning Star mine at Woods Point in alpine Victoria, many environmental and historical issues had to be evaluated.The site which had been derelict for 28 years had to be rehabilitated to a safe and aesthetically pleasing state prior to construction of a new operating mine site. Considerable liaison with government authorities and the local community was required.

Jan 1, 1992

Chemicals derived from petroleum raw materials satisfy so much of our industrial needs today that it is good to pause and realise two things -ò the petroleum chemical industry is so new, and the use of chemicals is a very old one.Petroleum is such an'abundant and convenient source of raw material that in little more than 30 years it has become the major source of supplyfor chemical rdanuf ctiree This paperw~l'l 'disc'uss t1.e main 'r`easons' for this rapid development by considering the : sub jest -under tkzree headings ea. Source of Raw Materials.b. The Impact of Petroleum Chemicals on Plant Design and Processes. ce Scme of the Major Chemicals Used Today.

Jan 1, 1962

By J A. Didovich

Near the completion of undergraduate studies, students in mining-related courses are increasingly being presented the opportunity to undertake postgraduate studies. The current boom in the mining industry, the shortage of young professionals entering the industry and the lucrative starting salaries and packages on offer makes this a difficult and perplexing decision. This paper will outline what a PhD entails, discuss the benefits that a PhD can provide and discuss the timing and mode of a PhD.

Jan 1, 2006

By F Shi, G Ballantyne, K Runge

There has been minimal innovation in the methods used to process an ore over the last 50 years. Productivity increases have largely resulted in increased equipment size without implementation of parallel improvements in technology. Complex orebodies of the future will need mining operations to adopt new technologies and techniques to make future ore treatment economically viable. Three emerging technologies, namely high voltage pulse (HVP) pretreatment, fine screening and the HydroFloat<sub>TM</sub> coarse particle flotation cell will be presented in this paper and the potential benefits that may result if they are adopted in mineral processing circuits will be outlined. The barriers that must be overcome before they can be adopted by industry with confidence will also be discussed. CITATION: Runge, K, Shi, F and Ballantyne, G, 2018. New technologies that will potentially enable processing of complex orebodies, in Proceedings Complex Orebodies Conference 2018, pp 126–129 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

Extensive geophysical exploration and drilling operations have been: conducted in, South Central Queensland by Phillips Petroleum Company and Sunray DX Oil Company since late 1959. The main outlines of subsurface geology are now known, but many problems must be solved before a comprehen sine. picture can be presented of the geology and petroleum prospects e Interpretations to date suggest that -fiddle Paleozoic sedimentary rocks, probably, related to the Tasman belt of geosynclines, once extended. over. most. of the area An oro;eny 2.n late Paleozoic time, succeeded by deep pre-Pexmian erosion, removed the older sediments over large. areas, but Paleozoic sediments, were preserved from erosion in the Adavale and ancillary structur-a.l basins. Marine sediments of Devonian age are con-sidered prospective source beds for petroleum. Current work is directed toward finding favorable structure and reservoir beds to test the oil prospects of the area.

Jan 1, 1962

By P Scott

Kaltim Prima Coal, an open cut coal mine located in Sangatta, East Kalimantan, Indonesia, operates two deep pits and two shallow pits with a truck and shovel operation. KPC produced 17 Mt of coal in 2002 by removing 120 Mbcm overburden. Geochemical investigations have indicated 20 per cent of total waste rock is potentially acid forming; ie it has the potential to create acid mine drainage (AMD). In the early years of the KPC operation, the presence of AMD had been observed in the mined out areas and in the waste rock dumps as a result of sulfidic waste rock exposure. A strategy for management of AMD from waste rock was implemented involving: sampling, analysis, modelling, selective handling and validation of final dump covers. Samples of the waste rock lithologies are collected from exploration drill holes for geochemical analysis to determine their acid generating potential. The geochemical database is used to develop the waste rock model for the life of mine pit areas. The acid forming and non-acid forming waste rock is delineated for each mining bench area for selective handling and placement within the waste rock dump during the operational stage. Each mining bench is sampled and assessed to validate the model predictions. The final dump cover is sampled to meet strict Quality Assurance requirements to ensure non-acid forming waste material is used in the outer cover of the dump. The geochemical investigation of the waste rock is integrated with mine planning to design and construct the waste rock dump to minimise the risk of generating acid. This process links the exploration stage, operation stage, and rehabilitation stage for each Pit area. The paper briefly reports the waste rock characterisation, waste modelling and strategies used for management of acid drainage by KPC.

Jan 1, 2003

Throughout industry in Australia, time lost through work accidents and illness is three times greater than strikes. In 1978 in New South Wales alone, 400 workers died, 125,000 were injured, 6,000 were indust- rially deafened, and 3,800 people died of occupational cancer. It has been estimated that less than 10% of workers injured make claims for common law damages. The figure is probably in fact much lower than that. However, common law damages claims are starting to become a boom industry and employers are only now starting to see the effect of the increase in Claims. I predict that within 5 years the number of common law damages claims made will increase dramatically.

Jan 1, 1982

By D Reid, A Fourie, J Ayala

This paper discusses cone penetration test correlations for loose gold tailings that were developed within a critical state soil mechanics framework. The development of a new calibration chamber for cone penetration testing that consists of a modified triaxial cell is described. Some of the early development and commissioning issues that were encountered, as well as the solutions adopted are outlined, including the system to prepare the samples and to acquire high-quality data from the testing. Also, the triaxial laboratory testing required to achieve the critical state line is described, including some of the basic precautions considered necessary as good practice. Additionally, the system adopted for volume tracking of the calibration chamber sample is described, which is essential for ensuring a reliable state parameter comparison against the acquired cone penetration test data. Finally, some laboratory test data from the calibration chamber is plotted against the soil behaviour type charts currently available from various authors.

Jul 1, 2021

Owing to the 'creeps' and consequent movements in the mines, followed by the recent fire in the southern workings, the whole of the orebody above the 800 ft. level is now very much crushed and broken. The same applies to the hanging wall or overwall coutrny, which has subsided towards the workings, so that for some years past all development work within the lode has had to be carried out with extreme care.The continual but slow subsidence of the overburden into the stopes necessitates a periodical renewal of all gangways in the lode, and, as the subsidence amounts to as much as 60 ft. in places, these new gangways must necessarily pass through the mullock-filling of old stopes in addition to broken ore. They at times pass into the broken ground of the hanging-wall for some distance, where the orebody has widened underneath by the original folding and puckering.

Jan 1, 1932

By A Nixon

The Australian mining industry has changed dramatically over the past 20 years in terms of mining methods, mining equipment and human resource policies. The industryÆs approach to safety and health in terms of attitudes, style of legislation, and risk management techniques has also changed significantly. These changes have had and continue to have major impacts on the design of underground mine ventilation systems. In some areas, trends are clearly emerging. In other areas, mine ventilation planning remains very æreactiveÆ and is performing poorly in terms of providing a safe and healthy work environment at a reasonable cost. New concepts involving the role of ramps and shafts, the provision of refrigerated air, æventilation on demandÆ and newe gress and entrapment approaches are likely to be incorporated into mine planning and operating practices over the next ten years. This paper discusses these and other trends and identifies some likely future developments in the area of hardrock mine ventilation.

Jan 1, 2005